The type of applications running over the Internet has become quite diverse nowadays. Each type of application requires different approaches regarding the delivery of data packets, i.e. the data packets must be delivered before a certain deadline. Throughput-oriented applications for example aim to optimize the throughput of data packets aiming at a high-throughput. Latency-sensitive applications on the contrary aim to minimize the latency in order to achieve a zero queuing delay. Note however it is unavoidable that a trade-off needs to be made between zero-queuing delay and high-throughput.
Current window-based schemes are devoted to reduce queue oscillations caused by the transmission control protocol (TCP) or one of its variants, leading to so-called active queue management (AQM) schemes. These AQM schemes are however stochastic, resulting in a stochastic congestion window. Hence, either queue oscillations will remain resulting in queues that are empty for a large portion of time or uncontrolled queue oscillations occur leading to unpredictable delays. As a result the efficiency of forwarding packets on a link within a communication network is reduced drastically.
An approach to improve the efficiency through minimizing the latency is to signal the endpoint device about a congestion before a link is fully utilized. Moreover, in order to lift the efficiency even more, a fraction of the capacity of the link can be sacrificed such that oscillations can be absorbed better. This approach is applied by the High-bandwidth Ultra-Low Latency (HULL) architecture which is an extension of a Data Centre Transmission Control Protocol (DCTCP). This architecture modifies the legacy window-based protocol via spacing data packets at an endpoint and by signalling congestion before a link is fully utilized.